A clown sighting were made near elementary schools in Hamden and Waterbury. (WFSB)

HAMDEN, CT (WFSB) -

Police have received reports of clown sightings near schools in Hamden and Waterbury on Thursday morning.

In Waterbury, a group of fourth graders at Carrington Elementary School reported to their teachers that they saw a clown outside during recess.

Officers were called to the school on Kenmore Avenue around 12:15 p.m. Police said they searched the area, but were unable to locate any clowns.

During the search, Carrington Elementary School was placed on lockdown. However, the lockdown was lifted after about 15 minutes.

There was a police presence still on the scene at 1 p.m. Parents were being notified about the incident and the board of education is monitoring the incident.

Earlier in the day, a teacher spotted a clown near Bear Path Elementary School, also in Hamden. The teacher told police about the sighting as they arrived for work around 7:30 a.m., police said.

Officers searched the surrounding area and no clown was located by police.

Extra officers were called to patrol all schools in Hamden. An extra officer was on duty at Bear Path Elementary School on Thursday.

Hamden Police Chief Thomas J. Wydra urged citizens to stop engaging in this "nonsensical behavior," especially on school grounds. Wydra added that "teachers have a difficult job and do not need these interruptions to their and their students' day."

The Ansonia Police Department arrested a 16-year-old girl on Wednesday morning in connection with a threat involving clowns made against Emmett O’Brien Technical High School. Ansonia police also charged two 13-year-old girls with making threats directed at the Ansonia School System.

The police department in Naugatuck said it arrested two 14-year-old on Tuesday for threats that referenced schools there.

A 13-year-old student from Region 16 School District was arrested for making threats posted on Instagram involving clowns on Tuesday night. The boy, who is from Beacon Falls, made "no specific threat of violence was made towards any student or schools," however, the posts identified schools in Prospect, Beacon Falls, Waterbury and New Haven.

There have been increased police presences at schools throughout the state including Simsbury, Wallingford and North Haven.

School officials in New Britain sent a letter to parents on Thursday, saying they have been working with police regarding postings on social media related to people dressing in clown outfits throughout the week.

"We ask that if your child texts you during the school day regarding this, you call the school to relay the message. Together, the school and you need to assure our students that they are safe and that we will take care of them," Superintendent of Schools Nancy Sarra said in the letter.

She said marked police cars will be increased at all neighborhoods to ensure that students feel safe while walking to and from school.